Sergei Pisarev: I very much hope that there is still something we don't know about nature

Arctic.ru has discussed modern methods for studying Arctic Ocean waters and the possible causes of rising temperatures with Sergei Pisarev, Head of the Polar Oceanology Group at the Russian Academy of Sciences’ Institute of Oceanology, Honorary Polar Explorer of the Russian Federation and PhD (Physics/Mathematics).

Mr. Pisarev, you have been studying the state of the Arctic basin's upper water masses for many years…

I have been doing this since 1982.

That's almost 35 years! Would you say that the state of Arctic waters has changed considerably during these observations? And what have these changes been?

Yes, the Arctic's upper water masses have been changing since the 1990s. In short, these processes amount to "warming." We can talk about the warming of intermediate Atlantic Ocean waters entering the region and about the desalination of upper polar/Arctic waters. Although they don't become warmer and hover around the freezing point, they are subject to changes linked with warming.

Could you explain, at what minimal depth are lower water masses located? And what is their current state?

According to generally accepted standard classification, they are located below 1,000 meters. To be honest, this presents a certain mystery associated with the fact that most robotic devices measuring the characteristics of water masses operate in upper layers. Only separate expeditions, in which I am also involved, conduct measurements at lower levels. One gets the impression that heat tends to sink deeper, but we still have no conclusive evidence making it possible to publish our findings.

Shouldn't heat rise to the surface according to the laws of physics?

No, in this case everything depends on the ocean's stratification. The Arctic basin is a major problem because some experts believe that the obviously warmer intermediate Atlantic Ocean waters transfer heat to the surface and influence the area of Arctic sea-ice formations. Others are at a loss as to how to explain this process, and they are also right because the ocean has a stable stratification and because a halocline exists in the Arctic. I'll explain. If Atlantic Ocean waters are like a heater inside a room, then the ice which is being heated is located somewhere beyond that room's wall. A tarpaulin wall quickly lets through heat, and the wall of a wooden hut keeps the heat inside. The Arctic halocline, that is, a layer of water with surging salinity levels, and in the Arctic also water density levels, plays the part of this wall. It's like a lid. And we can see that Atlantic Ocean waters are becoming warmer, and this "lid" is growing thicker as well. But the heat seeps through this "lid" in some areas along the continental shelf. However, the Arctic Ocean is large, and the "lid" only becomes stronger in some sectors and keeps the heat inside.

Why doesn't the heat just rise to the surface? Ocean waters intermix, sending heat flows in any direction because, for example, there are internal currents.

Deep-sea measurements are a daunting task because they require heavy-duty winches that can only be installed on powerful vessels. Only icebreakers can act as these powerful vessels in the Arctic, and it costs a lot to operate them.

And what equipment do you use?

Since the 2000s, we have started actively using unmanned robotic systems that measure physical and certain chemical parameters of the atmosphere, ice formations and upper ocean waters, working from one to three years. They operate automatically, and in terms of the obtained information, they exceed all the Soviet-era drifting stations ten times over.

There are plenty of unmanned robotic systems operating in the Arctic, which relay data to us via satellites. Each day, computers at an office of the Institute of Oceanology, including my own computer, show at least 40 profiles of vertical temperature distribution and deep-sea water salinity levels from the Central Arctic. In turn, the crew of the North Pole 1 drifting station, headed by Ivan Papanin, measured 37 such profiles during their nine-month expedition in 1937-1938.

It turns out that humans no longer have to be involved in measuring certain parameters of the Arctic. Many other biological projects still call for manual work, but various physical parameters, including electric conductivity, currents, temperatures, drift and sound speeds, visual images, and the thickness of ice and snow, are measured automatically.

But robotic equipment should be foolproof and must be installed by professionals. My experience shows that, instead of growing smarter, humans become duller while working in subzero temperatures. Therefore we need extremely sturdy equipment that is hard to break. Unfortunately, almost all our equipment is foreign-made.

Are our developers ready to offer something new?

First of all, such plans exist, and this is already good. Second, we realize that it's not good to lag behind to such an extent because Russia is a long-standing Arctic power. This is not just a sphere of our national interests; this is part of our life. All you have to do is look at the map.

Despite various plans, we have just two simple operational devices. One of them reliably transmits coordinates, which is also very important. You plant many of these devices on ice-floes, and they tell you about their location. This makes it possible to monitor the direction of ice drifts. The second rather unsophisticated device is also quite reliable. It transmits coordinates and temperatures inside the upper 10-20-meter ocean layer. Hopefully, we will receive more operational devices in the future.

In November 2015, Paris hosted the 21st UN Climate Change Conference, with its participants signing an agreement to set a goal of limiting global warming to less than two degrees Celsius compared to pre-industrial levels.It goes without saying that water and air temperatures are interlinked. Is there any way to prevent an increase in water and air temperatures?

Obviously, the Arctic nature is sending us a powerful signal. Regardless of whether this signal has been caused by the human race generating large amounts of carbon dioxide or by the Sun's influence, there are many theories — it is easier to study this signal than many other weak signals. Working within the sphere of my interests, I receive this signal and try to evaluate changes. I support the conference's decision and the signing of the agreement by Russia. But as an individual who does not professionally address this issue, I have some doubts. Actually, industrial countries vote to reduce toxic emissions at production facilities because this pollutes the environment. At the same time, underdeveloped economies with malnourished populations request funding for production modernization projects. This is a very concise description. I don't know how people will reach an agreement, and how they will restructure their production patterns, but this is a layman's viewpoint. Of course, we need to stop littering and cut back on carbon dioxide emissions, but I don't know whether this is possible. I don't see any of the pre-conditions so far.

And I very much hope that there is still something we don't know about nature; I hope that this unknown factor will balance the climate, and that temperatures will drop, at long last.